# Copyright (c) 2019, NVIDIA CORPORATION. All rights reserved.

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
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#     http://www.apache.org/licenses/LICENSE-2.0

# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
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# Neural Mesh Renderer

# MIT License

# Copyright (c) 2017 Hiroharu Kato
# Copyright (c) 2018 Nikos Kolotouros
# A PyTorch implementation of Neural 3D Mesh Renderer (https://github.com/hiroharu-kato/neural_renderer)

# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
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# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:

# The above copyright notice and this permission notice shall be included in all
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from __future__ import division
import math

import torch


def normalize_vertices(vertices):
    """
    Normalize mesh vertices into a unit cube centered at zero.
    """
    vertices = vertices - vertices.min(0)[0][None, :]
    vertices /= torch.abs(vertices).max()
    vertices *= 2
    vertices -= vertices.max(0)[0][None, :] / 2
    return vertices
